Fig 1. C4 interacts with multiple members of the Arabidopsis SHAGGY-like protein kinase family.

A. Yeast two-hybrid growth curve analysis of BCTV C4 interactions with 10 AtSK family members. C4 was fused to the GAL4 activation domain and the AtSK family members and Lamin C (negative control) were fused to the GAL4 DNA binding domain. Cells were grown in quadruple dropout media at 30°C and their optical densities at A₆₀₀ were measured. Each time point for each curve was obtained from three independent biological replicates run in triplicate. B. Confocal micrographs showing the interactions between C4-cEYFP and sg2AtSK-nEYFPs or AtSK41-nEYFP in BiFC assays following co-agroinfiltration into transgenic N. benthamiana CFP-H2B marker plants. From left to right, the first column shows the interaction assay EYFP signal (EYFP), the second the nuclear CFP-H2B reference signal (CFP-H2B), and the third the merger of both fluorescent signals with autofluorescence from chloroplasts (Overlay). Regions of co-localization appear yellow in the overlay. The known nYFP-N and cYFP-P interaction was used as a positive control [38] and GST-nEYFP [17] and C4-cEYFP were used as negative controls. Areas within the white boxes in the Overlay images are magnified in the Enlarged images. Arrowhead, chloroplasts. Scale bar = 50 μm.